IF YOU LOOK behind the headlines it becomes clear that it is not just the lowest wage earners who are being hit by soaring property prices. Even households with an income bracket of £25,000 to £40,000 are now finding themselves unable to afford to make the move from renting to buying. This problem is particularly acute in London and the South East.

As a result, there is now an urgent need for good quality, desirable housing that can be produced at a low cost. It is essential that this challenge is met if low and middle-income families are to have a chance of moving onto the property ladder and ensure the market does not stagnate.

As if this challenge wasn’t tough enough, providing well-constructed, cheaply produced housing is no longer enough to meet market demands. By 2050 the government hopes to reduce carbon emissions in the UK by 60% relative to 1990 levels and there is a real pressure on contractors to reduce their carbon footprint during the build and the lifetime of the building.

What can the construction industry do to meet this challenge?

Concrete buildings have been around since Roman times, but they have recently had a difficult time winning over the public’s affections in the UK. However, this much maligned material is extremely economical and, thanks to its suitability for pre cast and off site construction methods, has become the material of choice for a sustainable, affordable housing project in the East End of London.

Sutton’s Wharf Project, East London

A new £60m housing project at Sutton’s Wharf, Bow, East London, will see 419 new homes constructed in two years and is the result of a collaboration between Team and Elcon. The development will be a mixture of social rented, intermediate and open market accommodation and will also include a health centre, nursery and convenience store.

Tower Hamlets, the London Borough in which Bow sits, is one of the most densely populated in both England and Wales and the population will continue to rise over the coming years. While the borough is generally very deprived in comparison to the rest of London there has been a recent rise in the number of residents working in professional services, so housing that can accommodate both low and medium earners is in high demand.

Team was created in 2003, in response to the lack of good quality, affordable housing in the South East. The company designs and builds homes for people on intermediate incomes who want low cost accommodation in areas with easy access to places of work.

The regeneration of derelict land is a priority, so all of Team’s housing is built on either brownfield sites or on land that has previously been developed. To keep the price of their housing down and to reduce the impact on the environment of both the construction process, and the finished buildings, the focus of each project is firmly on efficiency.

Team plans to build its project at Sutton’s Wharf using the Elcon Building System, which is based on a production-line style operation designed to speed up the construction process.

Workforce

The Sutton’s Wharf project will not only provide reasonably priced housing in an area where it is desperately needed, but will also play a part in easing another of the borough’s major problems as it has the highest unemployment rates in the capital.

Construction will be carried out by a semiskilled work force supervised by a small number of experienced, specialised managers. Consequently it has been possible to recruit the majority of the project’s staff from among the local area’s unemployed community. These new recruits are currently receiving full training in construction  skills and plant operations. Team plans to recruit more people throughout the duration of the project.

The speed of construction will also keep the costs of the Sutton’s Wharf project down, ultimately translating into more affordable housing for the buyer. But how is this achieved on the ground?

The building at Sutton’s Wharf will be constructed using Elcon’s Lshaped concrete wall panels, which will be produced offsite and then transported to the construction site. Once building begins, the panels will be cast and delivered to the site at a rate which allows six apartments to be constructed every five days.

Staircases, lintels and feature panels will also be constructed offsite, which will save time during the construction process. The building will be enclosed at an early stage so work will be less prone to weather-related delays.

Similarly, the patented casting technique used in the production of the panels creates an even finish meaning there will be no need for wet trades such as rendering or plastering once the apartments are constructed. This will reduce the amount of time it takes for each unit to be fully completed.

The L-shaped panels are free from joists, which makes them more rigid. This means all walls are capable of being load-bearing structures, which makes the design of floors less problematical. With most systems, internal walls are not load-bearing, which limits the number of walls that can give support to the floors and consequently puts restrictions on the design.

The self-supporting nature of the L-shaped panels will also benefit the construction process. Lifting the panels and placing them into position by crane will require an average of three people, as supporting stays or props are not required and the process will take a matter of minutes. The building at Sutton’s Wharf will be constructed as quickly as the panels can be produced and the site craneage allows, resulting in time and cost savings.

The main structural wall and floor components are connected to each other by a system of reinforcing bars that act as couplings and reinforcement between the connecting members. The bars are bonded into vertical structural steel tubes using a high performance expanding grout. Precast floor planks are located over the protruding vertical bars from the panels below, and the wall panel is also located over the protruding bar so that the bar houses into the tube within the wall panel.

Meeting the Sustainability Challenge

The panels will be produced only one mile from the Sutton’s Wharf site and both factory and site are located next to canals. Many of the panels will be transported from the factory to the construction site on industrial barges, which will reduce the amount of fossil fuels burnt during the project and minimise the environmental impact of the build.

The Sutton’s Wharf project is the first time that the canals of London will have been used to deliver the main structural components for such a project for over 50 years.

Once the structure is complete, the thermal mass of the pre cast concrete walls and floors can also be used as fabric energy storage, which reduces the heating requirement in the winter and the cooling requirement in the summer. This feature of concrete will be a very important factor in buildings in the future given the predicted rises in environmental temperatures. Solar gain and air ventilation technology can also be retrofitted into the structure.

There is currently a gap in the market for quality accommodation for those on low and medium incomes. The speed at which the Team project at Sutton’s Wharf will be built means that it is likely to cost a lot less than it would if the complex was built using traditional construction methods.

The conflicting demands for more affordable housing and increasing environmental awareness all signify that concrete is well placed to make a return to the UK housing market.